The present invention relates to an ink liquid supply system for an ink jet system printer and, more particularly, to an ink liquid supply system which can remove bubbles included within the ink liquid to be supplied to a nozzle.
In order to obtain a clean printing in an ink jet system printer, especially in an ink jet system printer of the charge amplitude controlling type, it is necessary that uniform ink droplets are emitted from a nozzle at a given rhythm. When bubbles are contained in ink liquid supplied to a nozzle, the drop formation rhythm adversely is influenced and, therefore, print distortion will be created.
A typical ink liquid supply system is disclosed in U.S. Pat. No. 4,007,684 "ENTITLED INK LIQUID WARMER FOR INK JET SYSTEM PRINTER", issued on Feb. 15, 1977. In an ink jet system printer of the charge amplitude controlling type, ink droplets not contributing to printing operation are collected by a beam gutter and recirculated. Therefore, it is inevitable that bubbles are included in the ink liquid to be supplied to the nozzle.
In the conventional ink jet system printer of the charge amplitude controlling type, an air trap is interposed within the ink liquid supply system to remove large bubbles contained in the ink liquid. However, small bubbles are not removed in the conventional ink liquid supply system. Moreover, filter means are provided in the conventional ink liquid supply system to remove dust contained in the ink liquid but not to remove bubbles contained in the ink liquid to be supplied to the nozzle.